Fostering research in pediatric interventional radiology: needs assessment and suggestions for support

BACKGROUND

Due to the rarity of pediatric diseases, collaborative research is the key to maximizing the impact of research studies. A research needs assessment survey was created to support initiatives to foster pediatric interventional radiology research.

OBJECTIVE

To assess the status of pediatric interventional radiology research, identify perceived barriers, obtain community input on areas of research/education/support, and create metrics for evaluating changes/responses to programmatic initiatives.

MATERIALS AND METHODS

A survey link was sent to approximately 275 members of the Society for Pediatric Interventional Radiology (SPIR) between May and October 2020. Data was collected using a web-based interface. Data collected included practice setting, clinical role, research experience, research barriers, and suggestions for future initiatives.

RESULTS

Fifty-nine surveys were analyzed with a staff physician survey response rate of 28% (56/198). A wide range of practice sizes from 15 countries were represented. Respondents were predominantly staff physicians (95%; 56/59) with an average of 11 years (range: 1-25 years) of clinical experience working at academic or freestanding children's hospitals. A total of 100% (59/59) had research experience, and 70% (41/58) had published research with a mean of 30 peer-reviewed publications (range: 1-200). For job security, 56% (33/59) of respondents were expected or required to publish, but only 19% (11/58) had research support staff, and 42% (25/59) had protected research time, but of those, 36% (9/25) got the time "sometimes or never." Lack of support staff, established collaborative processes, and education were identified as top barriers to performing research.

CONCLUSIONS

The needs assessment survey demonstrated active research output despite several identified barriers. There is a widespread interest within the pediatric interventional radiology community for collaborative research.

Congenital Portosystemic Shunts: Variable Clinical Presentations Requiring a Tailored Endovascular or Surgical Approach

Congenital portosystemic shunts (CPSS) are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation. These shunts allow intestinal blood to reach the systemic circulation directly, and if persistent or large, may lead to long-term complications. CPSS can have a variety of clinical presentations that depend on the substrate that is bypassing hepatic metabolism or the degree of hypoperfusion of the liver. Many intrahepatic shunts spontaneously close by 1 year of age, but extrahepatic and persistent intrahepatic shunts require intervention by a single session or staged closure with a multidisciplinary approach. Early detection and appropriate management are important for a good prognosis. The aim of this case series is to describe the varied clinical presentations, treatment approaches, and outcomes of 5 children with CPSS at our institution. Management of these patients should involve a multidisciplinary team, including interventional radiology, surgery, hepatology, and other medical services as the patient's clinical presentation warrants. Regardless of clinical presentation, if a CPSS persists past 1-2 years of age, closure is recommended.

Use of Point-of-Care Ultrasonography in the NICU for Diagnostic and Procedural Purposes

Point-of-care ultrasonography (POCUS) refers to the use of portable imaging performed by the provider clinician at the bedside for diagnostic, therapeutic, and procedural purposes. POCUS could be considered an extension of the physical examination but not a substitute for diagnostic imaging. Use of POCUS in emergency situations can be lifesaving in the NICU if performed in a timely fashion for cardiac tamponade, pleural effusions, pneumothorax, etc, with potential for enhancing quality of care and improving outcomes.

In the past 2 decades, POCUS has gained significant acceptance in clinical medicine in many parts of the world and in many subspecialties. Formal accredited training and certification programs are available for neonatology trainees as well as for many other subspecialties in Canada, Australia, and New Zealand. Although no formal training program or certification is available to neonatologists in Europe, POCUS is widely available to providers in NICUs. A formal institutional POCUS fellowship is now available in Canada. In the United States, many clinicians have the skills to perform POCUS and have incorporated it in their daily clinical practice. However, appropriate equipment remains limited, and many barriers exist to POCUS program implementation.

Recently, the first international evidence-based POCUS guidelines for use in neonatology and pediatric critical care were published. Considering the potential benefits, a recent national survey of neonatologists confirmed that the majority of clinicians were inclined to adopt POCUS in their clinical practice if the barriers could be resolved.

This technical report describes many potential POCUS applications in the NICU for diagnostic and procedural purposes.

Trametinib for Refractory Chylous Effusions and Systemic Complications in Children with Noonan Syndrome

OBJECTIVE

To evaluate the effect of the RAS-MAPK pathway inhibitor trametinib on medically refractory chylous effusions in 3 hospitalized patients with Noonan syndrome.

STUDY DESIGN

Pharmacologic MEK1/2 inhibition has been used to treat conditions associated with Noonan syndrome, given that activation of RAS-MAPK pathway variants leads to downstream MEK activation. We describe our experience with 3 patients with Noonan syndrome (owing to variants in 3 distinct genes) and refractory chylous effusions treated successfully with MEK inhibition. A monitoring protocol was established to standardize medication dosing and monitoring of outcome measures.

RESULTS

Subjects demonstrated improvement in lymphatic leak with additional findings of improved growth and normalization of cardiac and hematologic measurements. Trametinib was administered safely, with only moderate skin irritation in 1 subject.

CONCLUSIONS

Improvements in a variety of quantifiable measurements highlight the potential utility of MEK1/2 inhibition in patients with Noonan syndrome and life-threatening lymphatic disease. Larger, prospective studies are needed to confirm efficacy and assess long-term safety.

Pediatric trauma and the role of the interventional radiologist

PURPOSE

While interventional radiologists occupy a critical role in adult trauma management, the role of interventionalist in pediatric trauma continues to evolve. The indications for transarterial embolization (TAE) are significantly different in pediatric patients in whom non-operative management (NOM) has a much more prominent role than in adults. Contrast extravasation on imaging may not require acute surgical or interventional management as it would in an adult. There are also areas in which pediatric interventional radiology is increasingly useful such as pelvic TAE in failed management, or splenic embolization to treat bleeding without the loss of splenic function inherent to surgical splenectomy. The rapid evolution of techniques and devices in pediatric patients is also changing what interventions are possible in pediatric trauma management which necessitates frequent reassessment of the guidelines and interventional radiology's role in caring for these patients.

CONCLUSION

This review seeks to consolidate the recent literature to describe the evolving role of the interventional radiologist in pediatric trauma management.

Extracorporeal membrane oxygenation as rescue therapy in a pediatric liver transplant recipient with very severe hepatopulmonary syndrome

BACKGROUND

In children with cirrhosis, the prevalence of HPS ranges from 3% to 20%, resulting in impaired gas exchange due to alterations in pulmonary microvasculature. LT is the gold-standard cure for cirrhosis complicated by HPS and should ideally be performed prior to the development of severe HPS due to increased risk for post-transplant hypoxia, right heart failure, and outflow obstruction.

METHODS

We present a case of a 13-year-old man, who underwent pediatric LT for severe HPS complicated by postoperative respiratory collapse, requiring a 92-day course of veno-venous ECMO.

RESULTS

Post-transplant, despite BiPAP, inhaled nitric oxide and isoproterenol infusion, he remained hypoxic postoperatively and acutely decompensated on postoperative day 25, requiring veno-venous ECMO. After 84 days on ECMO, a persistent large splenorenal shunt was identified that was embolized by interventional radiology, and 8 days after shunt embolization and ASD closure, he was successfully weaned off ECMO.

CONCLUSIONS

This case describes the longest known duration of ECMO in a pediatric LT recipient and a unique improvement in hypoxemia following a portosystemic shunt closure. ECMO presents a heroic rescue measure for pediatric LT recipients with HPS that develops acute respiratory failure postoperatively refractory to alternative measures.

The use of ultrasound in establishing COVID-19 infection as part of a trauma evaluation

Purpose

The use of lung ultrasound for diagnosis of COVID-19 has emerged during the pandemic as a beneficial diagnostic modality due to its rapid availability, bedside use, and lack of radiation. This study aimed to determine if routine ultrasound (US) imaging of the lungs of trauma patients with COVID-19 infections who undergo extended focused assessment with sonography for trauma (EFAST) correlates with computed tomography (CT) imaging and X-ray findings, as previously reported in other populations.

Methods

This was a prospective, observational feasibility study performed at two level 1 trauma centers. US, CT, and X-ray imaging were retrospectively reviewed by a surgical trainee and a board-certified radiologist to determine any correlation of imaging findings in patients with active COVID-19 infection.

Results

There were 53 patients with lung US images from EFAST available for evaluation and COVID-19 testing. The overall COVID-19 positivity rate was 7.5%. COVID-19 infection was accurately identified by one patient on US by the trainee, but there was a 15.1% false-positive rate for infection based on the radiologist examination.

Conclusions

Evaluation of the lung during EFAST cannot be used in the trauma setting to identify patients with active COVID-19 infection or to stratify patients as high or low risk of infection. This is likely due to differences in lung imaging technique and the presence of concomitant thoracic injury.

Complications of Percutaneous Renal Biopsy

Percutaneous renal biopsy is widely used for diagnosis, prognosis, and management of nephropathies. Complications may arise after renal biopsy, most commonly in the form of bleeding. Efforts should be taken to optimize modifiable risk factors such as hypertension, thrombocytopenia, and coagulopathy prior to the procedure. Unmodifiable risk factors such as poor renal function, gender, and underlying histologic diagnosis may be used to identify high-risk patients. Delayed presentation of bleeding complications is common, and close clinical follow-up is crucial.

Clinical Practice Guideline for the Management of Infantile Hemangiomas

Infantile hemangiomas (IHs) occur in as many as 5% of infants, making them the most common benign tumor of infancy. Most IHs are small, innocuous, self-resolving, and require no treatment. However, because of their size or location, a significant minority of IHs are potentially problematic. These include IHs that may cause permanent scarring and disfigurement (eg, facial IHs), hepatic or airway IHs, and IHs with the potential for functional impairment (eg, periorbital IHs), ulceration (that may cause pain or scarring), and associated underlying abnormalities (eg, intracranial and aortic arch vascular abnormalities accompanying a large facial IH). This clinical practice guideline for the management of IHs emphasizes several key concepts. It defines those IHs that are potentially higher risk and should prompt concern, and emphasizes increased vigilance, consideration of active treatment and, when appropriate, specialty consultation. It discusses the specific growth characteristics of IHs, that is, that the most rapid and significant growth occurs between 1 and 3 months of age and that growth is completed by 5 months of age in most cases. Because many IHs leave behind permanent skin changes, there is a window of opportunity to treat higher-risk IHs and optimize outcomes. Early intervention and/or referral (ideally by 1 month of age) is recommended for infants who have potentially problematic IHs. When systemic treatment is indicated, propranolol is the drug of choice at a dose of 2 to 3 mg/kg per day. Treatment typically is continued for at least 6 months and often is maintained until 12 months of age (occasionally longer). Topical timolol may be used to treat select small, thin, superficial IHs. Surgery and/or laser treatment are most useful for the treatment of residual skin changes after involution and, less commonly, may be considered earlier to treat some IHs.

Clinical Practice Guideline for the Management of Infantile Hemangiomas

Infantile hemangiomas (IHs) occur in as many as 5% of infants, making them the most common benign tumor of infancy. Most IHs are small, innocuous, self-resolving, and require no treatment. However, because of their size or location, a significant minority of IHs are potentially problematic. These include IHs that may cause permanent scarring and disfigurement (eg, facial IHs), hepatic or airway IHs, and IHs with the potential for functional impairment (eg, periorbital IHs), ulceration (that may cause pain or scarring), and associated underlying abnormalities (eg, intracranial and aortic arch vascular abnormalities accompanying a large facial IH). This clinical practice guideline for the management of IHs emphasizes several key concepts. It defines those IHs that are potentially higher risk and should prompt concern, and emphasizes increased vigilance, consideration of active treatment and, when appropriate, specialty consultation. It discusses the specific growth characteristics of IHs, that is, that the most rapid and significant growth occurs between 1 and 3 months of age and that growth is completed by 5 months of age in most cases. Because many IHs leave behind permanent skin changes, there is a window of opportunity to treat higher-risk IHs and optimize outcomes. Early intervention and/or referral (ideally by 1 month of age) is recommended for infants who have potentially problematic IHs. When systemic treatment is indicated, propranolol is the drug of choice at a dose of 2 to 3 mg/kg per day. Treatment typically is continued for at least 6 months and often is maintained until 12 months of age (occasionally longer). Topical timolol may be used to treat select small, thin, superficial IHs. Surgery and/or laser treatment are most useful for the treatment of residual skin changes after involution and, less commonly, may be considered earlier to treat some IHs.

Symptom Resolution and Volumetric Reduction of Abdominal Lymphatic Malformations With Sclerotherapy

BACKGROUND

Lymphatic malformations (LMs) are congenital and arise from errors in vascular embryogenesis. LMs are categorized by cyst size as microcystic, macrocystic, or combined. Abdominal LMs are rare. Surgical resection of abdominal LMs has been the mainstay of therapy, but recurrence and morbidity are high. We sought to determine the effectiveness of sclerotherapy treatment for abdominal LM.

METHODS

A single-center, retrospective review from 2014 to 2018 was conducted evaluating pediatric patients with abdominal LM.

RESULTS

Ten patients were included, n = 9 had macrocystic LM and one patient had combined disease. The average age at first treatment was 6.8 y. The most common presenting symptoms were abdominal distention, pain, infection, and anemia. Preprocedural imaging was performed for all patients; median pretreatment volume was 1572.9 cm³ (range, 67.2-13,226.4). LMs were accessed using ultrasound guidance and injected with opacified doxycycline. Patients received a mean of 7.1 sclerotherapy injections. Complications included intraperitoneal doxycycline extravasation (n = 1), managed conservatively, and LM infection (n = 1), treated with intravenous antibiotics and drainage. One patient went on to surgical resection due to inability gain stable intracystic access; follow-up ultrasonography showed no recurrence. Postprocedural imaging was available in n = 8. Volume decreased by 96.7% after sclerotherapy. The median remaining volume was 0 cm³ (range, 0-599.7) (P = 0.016). Postsclerotherapy magnetic resonance imaging was obtained in n = 6, with complete resolution in 83.3%. All patients had resolution of presenting symptoms. Follow-up duration was 12.3 mo.

CONCLUSIONS

Initial results demonstrate that sclerotherapy is an effective and durable treatment for symptom resolution and volume reduction of abdominal LM.

Female Pelvic Vascular Malformations

Vascular malformations are classified primarily according to their flow characteristics, slow flow (lymphatic and venous) or fast flow (arteriovenous). They can occur anywhere in the body but have a unique presentation when affecting the female pelvis. With a detailed clinical history and the proper imaging studies, the correct diagnosis can be made and the best treatment can be initiated. Lymphatic and venous malformations are often treated with sclerotherapy while arteriovenous malformations usually require embolization. At times, surgical intervention of vascular malformations or medical management of lymphatic malformations has been implemented in a multidisciplinary approach to patient care. This review presents an overview of vascular malformations of the female pelvis, their clinical course, diagnostic studies, and treatment options.

Percutaneous thoracic duct intervention to treat plastic bronchitis related to Fontan palliation

Plastic bronchitis is a life-threatening condition of airway obstructive cast formation. This pediatric case series from a high altitude center details the course of three patients after percutaneous thoracic duct interventions for refractory plastic bronchitis, with a follow-up interval of 3.5 years. In two patients, where cisterna chyli maceration (patients 2) or thoracic duct embolization (patient 3) was performed, a sustained clinical improvement is shown, with no subsequent cast recurrence. In patient 1, cisterna chyli maceration resulted in partial improvement. Herein, a favorable outcome is shown in pediatric patients with percutaneous thoracic duct interventions for plastic bronchitis at altitude.

Extratesticular masses in children: taking ultrasound beyond paratesticular rhabdomyosarcoma

Extratesticular cystic and solid scrotal masses are commonly encountered in pediatrics. The most common extratesticular malignancy is paratesticular rhabdomyosarcoma. The remainder of the common pathologies encountered -- appendage torsion, epididymitis and varicoceles -- are mostly benign. These frequently encountered benign lesions are confidently differentiated from paratesticular rhadbomyosarcoma using high-frequency scrotal sonography in combination with clinical features. Less commonly encountered extratesticular masses may not be as easily classified; however, these also have distinguishing features that can enable differentiation from malignancy. This review discusses the sonographic findings, and relevant clinical and pathological manifestations of the more unusual extratesticular masses encountered in two tertiary pediatric institutions during a 10-year period. While these extratesticular pathologies are encountered relatively infrequently, recognition of their manifestations enables appropriate management.